It is proposed to synthesize pheromone analogs in which a CH2 group adjacent to one or more double bonds of the pheromone is substituted by CF2. The presence of the fluorine atoms is not expected to change the dimensions of the resulting molecules, but the electro-negativity of fluorine is bound to have considerable effect on the nucleophilicity of the double bonds. Since the latter are most likely sites of interaction with pheromone receptors, the resulting molecules may show interesting and unusual biological properties. The chemistry required to prepare the proposed compounds is novel and has been developed in our laboratory. Inquiry with leading authorities in the field of insect pheromone biology has shown considerable interest in these substances.